Nanomodified NiFe- and NiFeP-carbon felt as anode electrocatalysts in yeast-biofuel cell

The improvement of the electron transfer from the microorganisms to the anode is considered to be one of the most important factors for increasing the biofuel cell efficiency. In our recent study, a significant improvement of the yeast-biofuel cell output was achieved by application of Ni-modified carbon felt anodes. In this study, the electrocatalytic properties of new nanomodified carbon materials were investigated. Nickel–iron and nickel–iron–phosphorous nanostructures were electrodeposited on carbon felt by means of pulse plating technique. The produced materials were analyzed for cytotoxicity and applied as anodes in a double-chamber mediatorless yeast-biofuel cell. The use of all modified electrodes resulted in increase of the biofuel cell outputs in comparison with those obtained with non-modified carbon felt; however, higher maximum power density values, exceeding up to 5-folds that of the control, have been achieved with NiFeP-carbon felt anodes. The observed electrocatalytic effects were connected with the particular elemental content, size distribution, and morphology of modified materials as well as with a hypothesis for switching on adaptive mechanisms as a response to Ni and Fe presence, resulting in facilitated electron transfer across the cell membrane.